10. "I will invite you." a. He says that b. He said that

Решение:

Преобразуем прямую речь в косвенную. Прямая речь содержит глагол "will invite" (Future Simple). Вводная конструкция "He says" – Present Simple, "He said" – Past Simple. При переходе в косвенную речь, если вводная конструкция в Past Simple, "will" меняется на "would" (Future Simple -> Future Simple in the Past).

• 10.a. He says that he will invite you.
• 10.b. He said that he would invite you.

Ответ:

• 10.a. He says that he will invite you.
• 10.b. He said that he would invite you.